Ultrasound Dyeing of Polyester Using Natural Colorant from Melastoma malabathricum l.

This paper reports on the application of natural dyes on polyester fabric. Melastoma malabathricum l. was extracted using conventional method of boiling for an hour. Plain lightweight polyester fabric was treated with sodium hydroxide as an alkaline treatment and Chitosan prior to dyeing in an attempt to increase the dye uptake. The dye extract of Melastoma malabathricum l. was applied on the polyester fabric at 85°C for an hour by exhaustion dyeing and 40 minutes for ultrasound dyeing. The colors of the dyed fabrics were measured using colour spectrophotometer and evaluated for washfastness. Ultrasound dyeing gave deeper colour shades to the fabric even though dyeing was conducted at lower temperature for 40 minutes. The alkaline treated fabrics dyed using ultrasound gave lower value of L* which indicate higher dye uptake and darker colour. The ratings for colourfastness to washing were between 4/5 to 5.

Ultrasonic Dyeing of Silk Fabric with Dirinaria picta Lichen Species

The aim of this work is to enhance dyeing efficiency and fastness properties of natural dyes from Dirinaria picta lichen species using ultrasound method. The dyes were extracted using boiling water, ammonia fermentation and solvent extraction methods. The time and temperature of ultrasound dyeing on silk fabrics were varied and compared with conventional dyeing. The results revealed that the efficiency of ultrasound dyeing is better than conventional dyeing in terms of giving darker shades on the fabrics. Ultrasound dyeing has the advantage of using lower dyeing temperature. The results of fastness properties to washing, perspiration, crocking and light were fair to good.

Influence of Ultrasonic on the Dying Properties of Cotton Fabric by Using Turmeric as Dye

In the process of using dye turmeric, the behavior of conventional dyeing and ultrasonic dyeing were compared. The processing of conventional dyeing and ultrasonic dyeing, such as dyeing time, dyeing temperature, pH value, and the amount of salt on the effect of K/S value, were investigated. The results show that the dye-uptake was greatly improved by using ultrasound. Meanwhile, the ultrasound dyeing was demonstrated more dominant in energy saving.

Investigation of Ultrasonic Effects in Cotton Dyeing Processing

Ultrasound can promote the dye-uptake in the dyeing process. The effects of ultrasound on the fiber, dye and dyeing system were investigated by dyeing cotton fabrics with a direct dye. The dye exhaustion exceeded 80% in 30 minutes with the assistant of ultrasound. Langmuir adsorption model could descript the ultrasound dyeing process of direct dye. The area of fiber accessibility of cotton fiber increased 1.68 times under the action of ultrasound. The absorbance of direct dye solution increased remarkably in the first 10 minutes of ultrasound irradiation. Ultrasound accelerated the diffusion of dye on cotton fiber, and then the diffusion coefficient increased 46 times